Opportunistic actions are less precise and certain than specified goals and intentions, but they result in less mental effort, less inconvenience, and perhaps more interest.
— The Design of Everyday Things by Donald Norman
This is a throw-away line that contains much, particularly in the “perhaps more interest.” He is talking about running errands and “oh, if you stop at the grocery store, could you pick up some plums?” but by now you should be familiar with the parallels between MMO quests and chores and errands.
“While I’m here” has long been the reason I get to bed late. Because we are finishing up this dungeon, oh maybe one more run to finish the achievement, and a resource node just respawned near the exit, and ooh is that a rare mob over there, and then I want to hit the vendor and the vault, and I can pick up another quest while I am here, and maybe I should process those crafting resources I picked up, and just two points to the next tier, and my plans ended before bedtime but it is now much later. A couple of those steps are embracing the illusion of scarcity, because you never know when you are going to find that rare spawn or when you are going to find such a good PUG, so gather ye rosebuds while ye may.
Opportunistic actions prevent the feeling of grinding. Even if you run through 20 of them, they are 20 unplanned opportunities to exploit. When you have a plan, you have a “to do” list, a set number of times to run the dungeon and earn badges or an expected 2% chance of getting that rare drop. You know what you are doing tonight, and it is just a matter of getting through it. “Getting through it” is not a mindset you want in your entertainment.
Of course, we are MMO players. Given events or public quests in random starting states, we will plan out grinds to make the night more efficient. You have these four events to complete to fill the bar and get the achievement, and you are really annoyed about needing to wait another 4:30 for the bandits to reset so you can get those wolves.